In recent years, in diagnosis using an endoscope, endoscope shape detecting apparatuses have come to be used for detecting a shape of an endoscope or the like inserted into a body or the like by using a magnetic field generating device and a magnetic field detecting device and displaying the detected shape by means of a display apparatus.
For example, Japanese Unexamined Patent Publication No. 2003-245243 and others disclose an apparatus for detecting the shape of an endoscope in insertion state by using a magnetic field and displaying the detected endoscope shape. In this apparatus, a plurality of magnetic field generating devices are driven which are disposed at predetermined intervals in an insertion portion of an endoscope to be inserted into the body to generate a magnetic field around the devices. This apparatus further detects respective three-dimensional positions of the magnetic field generating devices by means of magnetic field detecting devices disposed outside the body. The apparatus generates a curved line continually linking each of the magnetic field generating devices based on the three-dimensional positions thus detected, and displays on a display apparatus a modelled three dimensional image of the insertion portion.
By observing the image displayed on the display apparatus, an operator or the like can grasp the position of a distal end portion of the insertion portion inserted into the body and the insertion shape thereof, allowing the work of insertion to a target region or the like to be smoothly performed.
However, in the conventional endoscope shape detecting apparatus, the insertion shape of the endoscope is constantly displayed on the display apparatus. Therefore, during, for example, inspection using the endoscope image, the insertion shape image gets in the field of view in some cases even when it is not necessary to monitor the insertion shape image.
The present invention was made in view of the above-mentioned circumstances and an object thereof is to provide an endoscope shape detecting apparatus capable of displaying an insertion shape of the endoscope at a timing as needed.